Conventionally, an imaging apparatus is mounted on a vehicle such as an automobile to use an image taken by the imaging apparatus in driving and the like. For example, a place seen with difficulty from a driver's seat is imaged such that a driver may easily recognize an obstacle and the like by using an in-vehicle monitor and the like. In addition, an area in front of a vehicle body is continuously imaged to avoid an accident or verify a situation when the accident occurs based on an imaged image. Furthermore, there also is a case in which the imaging apparatus is installed outside and the image taken by the imaging apparatus is used as evidence information of a crime.
When the imaging apparatus is installed outdoor or outside the vehicle, the imaging apparatus is exposed to the atmosphere and a foreign material such as a droplet and dust adheres to a lens portion and the like, thereby narrowing a field of view of the imaging apparatus or generating blurring and the like of the imaged image. Therefore, in Patent Document 1, it is determined whether the foreign material or the droplet adheres to the lens based on the image taken by the imaging apparatus to drive a wiper.